body, html {
  margin: 0px;
  padding: 0px;
}

#topo {
  margin: 0 auto;
  width: 800px;
  background-color: #cccccc;
  height: 180px;
  display: block;
}

#logo {
  float: left;
  width: 240px;
  height: 174px;
  margin: 3px;
  background-color: green;
}

#menu {
  float: right;
  width: 552px;
  background-color: red;
}